A really dumb question, I’m afraid - I’m sure I am missing something very simple.
I am designing a query on my names & addresses database which includes several ‘true/false’ fields. When I look at the result on screen to confirm it is doing what I want, the T/F fields are displayed as small squares. However, they have 3 styles instead of the two I would expect. Some contain a tick where I would expect to see one, some are empty where I would expect them to be empty; but some contain a solid black centre! These black ones seem to correspond to ‘false’ entries, but so do the empty ones. If I click on a black square I can cycle through a tick and a blank and back to black again. I have confirmed by trial and error that doing this does change the underlying data (ie if I turn a black square to a tick, the corresponding record is edited to show ‘true’ in that field)
What do the black squares mean, and how can I stop them appearing?